TY - JOUR
T1 - The Lamont-Doherty Geological Observatory Isolab 54 isotope ratio mass spectrometer
AU - England, J. G.
AU - Zindler, A.
AU - Reisberg, L. C.
AU - Rubenstone, J. L.
AU - Salters, V.
AU - Marcantonio, F.
AU - Bourdon, B.
AU - Brueckner, H.
AU - Turner, P. J.
AU - Weaver, S.
AU - Read, P.
PY - 1992/12/1
Y1 - 1992/12/1
N2 - The Lamont-Doherty Geological Observatory (LDGO) Isolab 54 is a double focussing isotope ratio mass spectrometer that allows the measurement of thermal ions produced on a hot filament, (thermal-ionization mass spectrometry (TIMS)), secondary ions produced by sputtering a sample using a primary ion beam, (secondary ion mass spectrometry (SIMS)), and sputtered neutrals resonantly ionized using laser radiation, (sputter-induced resonance ionization mass spectrometry (SIRIMS)). Sputtering is carried out using an Ar primary beam generated in a duoplasmatron and focussed onto the sample using a two-lens column. Resonance ionization is accomplished using a frequency-doubled dye laser pumped by an excimer laser. The Isolab's forward geometry analyzer, consisting of an electrostatic followed by a magnetic sector, allows the simultaneous collection of different isotopes of the same element. This instrument is the first to have a multicollector that contains an ion-counting system based on a microchannel plate as well as traditional Faraday cups. A second electrostatic sector after the multicollector is equipped with an ion-counting Daly detector to allow high abundance sensitivity for measurements of large dynamics range. Selectable source, collector, α and energy slits on the instrument allow analyses to be made over a range of mass resolving powers and analyzer acceptances. Recent applications of the instrument have included the analyses of U by TIMS, Hf, Th and Re by SIMS and Re and Os by SIRIMS.
AB - The Lamont-Doherty Geological Observatory (LDGO) Isolab 54 is a double focussing isotope ratio mass spectrometer that allows the measurement of thermal ions produced on a hot filament, (thermal-ionization mass spectrometry (TIMS)), secondary ions produced by sputtering a sample using a primary ion beam, (secondary ion mass spectrometry (SIMS)), and sputtered neutrals resonantly ionized using laser radiation, (sputter-induced resonance ionization mass spectrometry (SIRIMS)). Sputtering is carried out using an Ar primary beam generated in a duoplasmatron and focussed onto the sample using a two-lens column. Resonance ionization is accomplished using a frequency-doubled dye laser pumped by an excimer laser. The Isolab's forward geometry analyzer, consisting of an electrostatic followed by a magnetic sector, allows the simultaneous collection of different isotopes of the same element. This instrument is the first to have a multicollector that contains an ion-counting system based on a microchannel plate as well as traditional Faraday cups. A second electrostatic sector after the multicollector is equipped with an ion-counting Daly detector to allow high abundance sensitivity for measurements of large dynamics range. Selectable source, collector, α and energy slits on the instrument allow analyses to be made over a range of mass resolving powers and analyzer acceptances. Recent applications of the instrument have included the analyses of U by TIMS, Hf, Th and Re by SIMS and Re and Os by SIRIMS.
KW - negative thermal ion mass spectrometry
KW - secondary ion mass spectrometry
KW - sputter-induced resonance ionization mass spectrometry.
KW - thermal ion mass spectrometry
UR - http://www.scopus.com/inward/record.url?scp=0000147898&partnerID=8YFLogxK
U2 - 10.1016/0168-1176(92)80063-7
DO - 10.1016/0168-1176(92)80063-7
M3 - Article
AN - SCOPUS:0000147898
SN - 0168-1176
VL - 121
SP - 201
EP - 240
JO - International Journal of Mass Spectrometry and Ion Processes
JF - International Journal of Mass Spectrometry and Ion Processes
IS - 3
ER -